This paper examines the distributional effects of monetary policy in 12 OECD economies between 1920 and 2016. We exploit the implications of the macroeconomic policy trilemma with an external instrument approach to analyze how top income shares respond to monetary policy shocks. The results indicate that monetary tightening strongly decreases the share of national income held by the top 1 percent and vice versa for a monetary expansion, irrespective of the position of the economy. This effect (i) holds for the top percentile and the ultrarich (top 0.1 percent and 0.01 percent income shares), while (ii) it does not necessarily induce a decrease in income inequality when considering the entire income distribution. Our findings also suggest that the effect of monetary policy on top income shares is likely to be channeled via real asset returns.